Thermal Analysis of Hard Ceramics
Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
Titanium carbonitrides (TiCxN1-x ) are known by their excellent properties. They are widely used in cutting tools and in the preparation of advanced engineering ceramic-based composites. It has been found that TiC0.3N0.7 is a precursor of carbon nitride (C3N4) which has a structure similar to that of Si3N4 and a hardness comparable to diamond. Due to the exciting potential of C3N4, a large effort has been put into synthesizing it. However to date, the synthesis of C3N4 as a crystalline material has not been achieved. This thesis work aims to crystallize C3N4 on SiC and Si3N4 substrates. Four different mixtures were studied in this project: TiC0.3N0.7/Si3N4 and TiC0.7N0.3/SiC with different molar ratios (2:1) and (1:1). Differential scanning calorimetry (DSC) and Thermogravimetry (TG) were first used in both nitrogen and argon gas in order to study the thermal behaviour of the mixtures and X-ray diffraction (XRD) was used afterwards to determine the composition of the new phases. DSC/TG results show that in argon atmosphere, the mixtures TiC0.3N0.7: Si3N4 (2:1) and TiC0.7N0.3: SiC (2:1) decompose at 1300 °C. While they decompose at 1450 °C in nitrogen atmosphere.XRD results indicate that at 1450 °C, TiC0.3N0.7: Si3N4 with molar ratios (2:1) and (1:1) decompose to SiC and TiN. Besides that, TiC0.7N0.3: SiC with molar ratio (2:1) decomposes to Si3N4 and Ti2N. The thermal analysis results show that TiC0.3N0.7/Si3N4 and TiC0.7N0.3/SiC might be interesting precursors for C3N4.
Place, publisher, year, edition, pages
2011. , 86 p.
Technology, Thermal Analysis, TiC0.3N0.7, TiC0.7N0.3, molar ratios, Si3N4, SiC, substrates, crystalline C3N4, DSC, TG, X-Ray
IdentifiersURN: urn:nbn:se:ltu:diva-44265Local ID: 20fb5b3d-220d-4df8-8937-2b4fc3ff5181OAI: oai:DiVA.org:ltu-44265DiVA: diva2:1017541
Subject / course
Student thesis, at least 30 credits
Materials Engineering, master's level
Validerat; 20110929 (anonymous)2016-10-042016-10-04Bibliographically approved